Benchmark: new Date() vs Date.now()

Script Preparation code:

var timestamp = null;

Tests:

Date.now()
timestamp = Date.now();
new Date()
timestamp = new Date()
performance.now()
timestamp = performance.now()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Date.now()
new Date()
performance.now()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:104.0) Gecko/20100101 Firefox/104.0

Browser/OS: Firefox 104 on Linux

View result in a separate tab

Test name	Executions per second
Date.now()	8331483.5 Ops/sec
new Date()	6320177.5 Ops/sec
performance.now()	4551100.5 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):

LLMs can make mistakes. Check important info.

I'll break down the benchmark test for you.

**What is tested:**

The benchmark tests the performance of three JavaScript methods to retrieve the current timestamp:

1. `Date.now()`
2. `new Date()`
3. `performance.now()`

These methods are used to measure the execution time and compare their performance across different browsers, devices, and operating systems.

**Options compared:**

The benchmark compares the performance of these three methods in terms of the number of executions per second (`ExecutionsPerSecond`).

**Pros and Cons:**

1. `Date.now()`: This method is relatively simple to use and widely supported by modern browsers. However, it may not be suitable for all scenarios, as its resolution is limited to milliseconds (100 nanoseconds). On the other hand, it's a lightweight option with minimal overhead.
2. `new Date()`: This method creates a new `Date` object, which can lead to slower performance compared to `Date.now()` due to the additional memory allocation and object creation. However, it provides more flexibility in terms of timestamp formatting and manipulation.
3. `performance.now()`: This method uses the `performance` API, which is designed specifically for measuring time-related metrics. It offers high-resolution timestamps (typically in the range of nanoseconds) and is generally faster than `Date.now()` or `new Date()`. However, its usage may require more expertise and browser support.

**Library:**

None of these methods use a specific library.

**Special JavaScript features/syntax:**

There are no special JavaScript features or syntax used in this benchmark. The tests only rely on basic JavaScript constructs (variables, function definitions, etc.).

**Other alternatives:**

If you need to measure time-related metrics, other alternatives include:

* `Date` object methods like `getTime()`, `getMilliseconds()`, and `getSeconds()`
* Browser-specific APIs like `window.performance.now()` or `navigator.performance.now()`
* Third-party libraries like Highcharts, Moment.js, or Date-fns
* Web performance measurement frameworks like WebPageTest or Lighthouse

Keep in mind that the choice of method depends on your specific use case and requirements.

**Benchmark preparation code:**

The provided `Script Preparation Code` is simple:
```javascript
var timestamp = null;
```
This initializes a variable `timestamp` without any initial value. The other test cases define the actual benchmark functions, such as `Date.now()`, `new Date()`, and `performance.now()`.

Related benchmarks:

new Date() vs Date.now() (version: 0)

Comparing performance of: Date.now() vs new Date() vs performance.now()

Created: 3 years ago by: Guest

Jump to the latest result

Date.now()

new Date()

performance.now()

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):